The invention relates to a folding top for a convertible vehicle.
Folding tops for convertible vehicles, which are fixed to the vehicle body by means of lateral guide linkages, and which can be displaced, positively controlled by the guide linkage, between a closed position covering the vehicle passenger compartment and an open position exposing the vehicle passenger compartment, are known in practice. A displacement of the folding top can in this case be automated by means of a drive device or can be done by manually swiveling the folding top. The extent of the folding top in the direction of travel is particularly large, particularly on convertible vehicles having two or more rows of seats. One problem here is that in the course of an opening movement the folding top first swings upwards and in so doing also covers a relatively large sweep in a vertical direction. The maximum height attained by folding top parts in the course of the travel movement defines a minimum clear overall height needed for opening the folding top, which must not exceed a normal garage height even in the case of a large folding top, so as to avoid damaging the folding top. At the same time parts of the folding top must not intrude into the vehicle passenger compartment in the course of the displacement movement, in order to exclude any risk of injury to the vehicle passengers.
FIGS. 11 to 16 show a convertible folding top 101 known from the state of the art. The folding top 101 is embodied as a fabric folding top and comprises a main guide link mechanism 104, embodied as a main four-bar linkage with a first main guide link 106 and a second main guide link 107. The main guide links 106, 107 are each mounted on a main bearing unit 105, which is fixed to the vehicle body and which forms the basis of the main four-bar linkage, allowing them to swivel at one end close to the vehicle body. A first folding top element 117 embodied as a roof frame element is in each case articulated in the area of an end of the first main guide link 106 and the second main guide link 107 remote from the vehicle body and forms a coupling link of the main four-bar linkage. Adjoining and in front of the folding top element 117 in the direction of travel is a second folding top element 119, which forms a second roof frame element and which when the folding top 101 is closed lies adjacent to a cowl 120 of the convertible vehicle. When the folding top is displaced from the closed position into the opened position, the second folding top element 119, the first folding top element 117 and the first main guide link 106 swivel in an z-shape into a rear stowage area, a front bow 121 arranged at the front end of the second folding top element 119, viewed in the direction of travel, describing an upwardly expanding trajectory curve, the maximum height of which defines the minimum clear overall height needed for opening the folding top. The folding top 101 comprises a drive element 127, which is embodied as a gas-filled compression spring and which assists a swiveling of the folding top 101. At a first end the drive element 127 acts on the first main guide link 106 and at its second end is supported on the main bearing unit 105. Starting from the closed position of the folding top, the drive element 127 first assists a swiveling of the first main guide link 106 counter to the direction of travel, until a middle position of the folding top is reached (FIG. 12). In this position of the folding top the drive element 127 is in a dead-point position relative to the first main guide link 106, so that no torque can be transmitted to the first main guide link 106. In this position the drive element 127 has reached its maximum adjustment travel. Further displacement of the folding top 101 towards the opened position causes the first main guide link 106 to swivel further counter to the direction of travel, so that the drive element 127 is deflected out of the dead-point position and is tensioned by the main guide link 106. The displacement movement of the folding top 101 is now correspondingly braked by the drive element 127. A disadvantage of the arrangement shown in FIG. 11 to FIG. 16 is that the folding top 101 needs a large clear overall height, since the front bow 121, particularly in a middle range of the displacement movement, rises up a long way.
DE 101 19 069 A1 describes a folding top for a convertible vehicle, which is embodied as a hard-shell folding top and which can be displaced by means of a drive device between a closed position and an opened position. The folding top has a main guide link mechanism embodied as a seven-bar linkage, which comprises a first main guide link and a guide link element, which are each articulated in a joint fixed to the vehicle body. A second main guide link is articulated on an end of the guide link element remote from the vehicle body. A roof element embodied as a middle roof shell part is in each case articulated on an end of the first main guide link and of the second main guide link remote from the vehicle body and couples these together. The main guide link mechanism further comprises a coupling link, which is articulated on the first main guide link on the one hand and on the guide link element on the other. The drive device in the form of a linear drive acts at a first end on the first main guide link and is supported at a second end in a pivot point fixed to the vehicle body. The distance from the point of action of the drive device on the first main guide link to the first pivot point of the first main guide link fixed to the vehicle body defines a first lever arm, by way of which the drive device introduces a torque into the main guide link mechanism. One disadvantage to this folding top arrangement is that a large clear overall height is needed for opening the folding top.
DE 10 2005 058 921 A1 describes a folding top for a convertible vehicle, which can be displaced between a closed position and an opened position. The folding top comprises a main guide link mechanism with a first main guide link and a second main guide link, which at a first end are each pivotally connected to a first roof part and at a second end are each pivotally connected to a console fixed to the vehicle body. The first main guide link, the second main guide link, the first roof part and the console together form a first four-bar linkage arrangement, having the console as its base and the first roof part as its coupling link. The folding top further comprises a drive kinematic chain, comprising a first, curved drive link and a second short drive link. At a first end the first drive link is articulated on the console of the folding top and at a second end it is pivotally connected to a first end of the second drive link. At a second end the second drive link has an articulated connection to the first main guide link, so that the first drive link, the second drive link, the second main guide link and the console together form a second four-bar linkage arrangement, having the console as its base and the second drive link as its coupling link. A swiveling of the second four-bar linkage arrangement can be driven by means of a linear drive unit embodied as a linear cylinder. At a first end the linear drive unit is supported in a pivot point on the console of the folding top and at a second end on the first drive link, and drives the latter directly.
DE 196 42 152 A1 describes a hard-shell folding top for a convertible vehicle, which can be displaced between a closed position and an opened position. The folding top comprises a first, rear roof part, a second, middle roof part and a third, front roof part. At a first end a first main guide link is swivel-mounted on a vehicle body and at a second end it is swivel-mounted on the first roof part. A linear drive unit embodied as a linear cylinder is articulated at a first end on the vehicle body and at a second end on a first end of a drive link. A second end of the drive link has an articulated connection by way of an intermediate guide link to the second roof part. The first roof part and the second roof part are pivotally connected to one another by a roof part guide link and additionally comprise a locking unit, which serves to lock the first roof part to the second roof part. To open the folding top, the first roof part is locked to the second roof part and the drive link is displaced by means of the linear drive unit, so that the first roof part and the second roof part are swiveled together, guided by the first main guide link. The locking of the first roof part and the second roof part is then cancelled and the second roof part is swiveled by displacement of the drive link below the first roof part.